This invention pertains generally to the display of video images and more particularly to a system and method for controlling the display of a plurality of images of moving objects.
Heretofore, electronic video amusement games have been provided in which images of objects are caused to move about on the screen of a video display tube under control of an operator or in response to control signals generated by circuitry within the game. One example of a system for controlling the position of an image in such a game is found in U. S. Pat. No. 3,793,483, issued Feb. 19, 1974 to the assignee herein.
In the past, a separate motion counting or comparator circuit has generally been required for each moving object to be displayed. With multiple objects, multiple counters or comparators are required, and this can result in relatively complex and expensive circuitry.
Summary and Objects of the Invention
The invention utilizes a single motion counting circuit or comparator for controlling the display of a plurality of moving images. Position data for the object is arranged at the outset of each frame according to the order in which the images are to appear in that frame. In one embodiment, numbers corresponding to the distance between successive images along the path of the beam are stored, and pulses corresponding to the position of the beam are counted to determine when the position of the beam corresponds to the locations at which the images are to be displayed. In a second embodiment, the image location data is compared with signals corresponding to the position of the beam to determine when the beam reaches the locations at which the images are to be displayed.
It is in general an object of the invention to provide a new and improved system and method for controlling the position of images on a video display screen.
Another object of the invention is to provide a system and method of the above character which are particularly suitable for use in video amusement games.
Another object of the invention is to provide a system and method of the above character utilizing a single counting circuit or comparator for controlling the display of a plurality of moving images.
Additional objects and features of the invention will be apparent from the following description in which the preferred embodiments are set forth in detail in conjunction with the accompanying drawings.